Multi-omics analyses indicate the involvement of jasmonic acid-associated signaling in N,N′-diacetylchitobiose-induced root growth in Pseudostellaria heterophylla

Pseudostellaria heterophylla has high medicinal value, yet poor plant growth restricts its cultivation. N,N′-diacetylchitobiose is a promising green biostimulant that promotes P. heterophylla growth. However, the molecular mechanism by which P. heterophylla responds to N,N′-diacetylchitobiose has not been elucidated. Herein, three concentration treatments (0.469, 2.340, and 9.376 μmol/L) combined with transcriptomic and metabolomic multi-omics analyses were performed. In total, 16470 DEGs were mainly enriched in signal-perception-related plant-pathogen interaction, signal-transduction-related plant hormone signal transduction, and secondary metabolic pathways. DAMs were predominantly mapped to secondary metabolism, amino acid metabolism, and hormone-associated α-linolenic acid metabolism (JA biosynthesis) and zeatin biosynthesis. Integrated omics and functional assays demonstrated that P. heterophylla responds to N,N′-diacetylchitobiose via a three‑tiered “signal perception‑signal transduction‑metabolic execution” cascade. Signal perception is mediated by plant‑pathogen interaction to trigger defense responses. Signal transduction is dominated by α‑linolenic‑acid‑dependent JA biosynthesis, proposed as the core initiating switch, and metabolic execution comprises downstream phenylpropanoid‑flavonoid secondary metabolism along with putatively synergistic cysteine and methionine metabolism. Elevated LOX and PAL activities at 48 h further validated this regulatory cascade. This cascade mediates the promotion of root growth upon N,N′-diacetylchitobiose treatment. These findings provide theoretical support for deploying N,N′-diacetylchitobiose as a biostimulant for the green cultivation of P. heterophylla .